Utah is considered to be an endemic area for hydatid disease, and more autochthonous cases of echinococcosis have been reported in Utah than in any other state in conterminal United States. The accumulated data for the prevalence of this disease in the state since this project started is: dogs, 32 of 128 examined (25.0 percent), sheep, 410 of 3,388 examined (12.1 percent); and humans, 4 of 368 examined (1.1 percent). Research in progress entails: (1) continued surveillance for Echinococcus granulosus in Utah, (2) assessment of temperature and moisture variations on the infectivity of protoscolices and eggs, (3) attempts to experimentally infect different wild and domestic carnivores to possibly identify natural reservoir definitive hosts in Utah, (4) assessment of chemotherapeutic agents against the adult tapeworms, and (5) development of cal-comp plotting techniques for meteorologic measurements associated with this project.